Periscaria perfoliata (formerly known as Polygonum perfoliatum) is on Pennsylvania's noxious weed list. Pennsylvania's Department of Conservation and Natural Resources classifies it as an invasive species, which is defined as "...those species that are not native to the state, grow aggressively, and spread and displace native vegetation. Invasive plants are generally undesirable because they are difficult and costly to control and can dominate whole habitats, making them environmentally destructive in certain situations."If you've ever encountered it, then you'll understand where it gets other common names like Devil's Tail and Tear-thumb.

Mile-a-Minute Vine Smothering a Blackberry Stand in Eckhart Landscape

It was probably introduced from imported nursery stock from its native habitat in East Asia, and first noticed in York County, Pennsylvania in the 1940's.It is an annual that is self pollinating, producing a small, blue berry that birds eat, spreading the seeds which can remain viable for years.Small infestations can be managed by pulling (wear gloves) or mowing, if it's growing in places without other desirable plants.

Mile-a-Minute Vine Smothering a Blackberry Stand in Eckhart Landscape

A pre-emergent herbicide, like products containing the active ingredient Trifluralin (Preen is one example) can be effective in managing its spread.A small weevil Rhinoncomimus latipesfrom China has been approved by the USDA for release as a biological control agent.As always when using pesticides, be sure to read the label and follow the directions.